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Comment Re: Good Summary Until... (Score 1) 258

Yep, the unstructured garage situation is a much better example than the poorly marked highway with missing markings or potential conduction areas. The sudden lack of GPS and maps is highly contrived anyway (!), and these conditions can be coped with fairly easily by analyzing traffic if other cars are around, staying on the right half of unmarked roads (dynamically calculating virtual lanes, something the software does anyway), recognizing obstacles and objects in motion around construction sites. These are all highly predictable situation that engineers can more or less easily integrate into their models, so to raise them as top level concerns seems very naive, especially for a supposed expert in the field.

Comment Re: Last quarter mile navigation (Score 1) 258

I've been thinking about that problem too. A good example would be unstructured situations, such as spill over event parking on lawns or gravel lots. Given existing cars cars already there certain pattern formation algorithms can be applied, such as continue this or that line of cars. Otherwise things get even trickier and some spacial user interface will have to let the passenger point out in an overhead view where exactly to place the car and in what orientation. None of these are unsolvable problems per se, but a lot of research is still ahead for sensible user interface and car interaction paradigms that can be elevated to standardized levels across makes so one can hop from one car to another and still operate it reliably. Perhaps even in completely autonomous vehicles such as the ones Google is experimenting with a fallback controller of some sort will always be needed.

Interesting times, for sure, and I'm glad I'm getting to live through them.

Comment Re:Electric. (Score 1) 659

Why stop there? Why not also object to tire friction, air friction etc? Let's not be pedantic here, the initial discussion was raw efficiency of the power plant, ICE vs electric motor, which basically means shaft output. You can significantly improve the overall efficiency of a system with a hybrid turbo-diesel setup where the TD drives a generator directly in its optimum power band, thus also gaining regen braking advantages etc. The most efficient setup may very well end up being a consumer targeted KERS system with a battery just big enough to always run the car electrically and a TDI engine just big enough to always keep the battery topped up. Long term of course a micro gas turbine could be the bestr answer, but those are only just starting to leave the R&D stages at small companies and aren't yet tested in high production volumes.

Comment Re:Electric. (Score 2) 659

> a GMC Yukon SLT that is nicer inside than most of what BMW, Audi, and Mercedes sells at that price point, it rides better

"Nicer" is truly in the eye of the beholder. I have yet to see an American vehicle whose interior doesn't--to me--scream cheap and amateurish plastic, your particular truck included. And "better ride" is also highly subjective. For me a better ride means a good amount of road feel without being jarring, good road feel through the steering wheel, a low center of gravity and the ability to take tight turns reliably and without losing traction or lots of body roll, etc. IOW the types of things a Yukon or Denali don't have a prayer in ever giving me, yet my lowly Jetta has in spades. I'm really not interested in tons of power since it's mostly pointless with our ludicrous speed limits. But I do want a stick shift so I can get really good 0 - 35mph times at the lights, which is where--let's face it--the real fun is! :D

Comment Re:Electric. (Score 3, Informative) 659

Here is a Wikipedia excerpt regarding modern turbo diesels, currently the most efficient automotive ICEs:

"Modern turbo-diesel engines are using electronically controlled, common-rail fuel injection, that increases the efficiency up to 50% with the help of geometrically variable turbo-charging system; this also increases the engines' torque at low engine speeds (1200-1800RPM)."

A 50% efficiency is pretty amazing and testament to over a century of dogged, steady improvement. We're approaching the theoretical maximum efficiency of the ICE.

Comment Follow the money... (Score 4, Informative) 109

My gut instinct says that very rarely do people in the public eye follow totally altruistic agendas, particularly when it comes to issues like this that have little to do with the common good. If you dig deep enough you can find special interest trails that more often than not uncover these people's true motivators. Just follow the money.

Comment Re: follow the money (Score 2, Insightful) 334

You're exactly right! I've done tons of "exploratory" coding over the years myself, either using some new techniques or new products, just for the fun of it or to learn something new. But that would always be on small, low visibility projects where the consequences of potential poor performance or other issues would be insignificant. To tread new ground on something so big with national visibility is foolish. You'd want the most well established and known reliable and performant tools and techniques possible. I played around a bit with these object based databases in the early days, and for some uses such as simple dictionary type access to a serialized object they're good. But the query syntax is almost always XPath oriented and less than optimal for complex joins such as you would find in massive systems like this. I guess they've learned their lesson now.

Comment Re:That's fine and dandy (Score 1) 289

I was mainly addressing your jackass "you obviously don't..." response to the guy above. As you mentioned the article contains no technical details, so neither you nor I have any basis for a great debate. Fact is only that various technologies DO exist to dramatically increase the effective throughput of optical drives, the question is only if any of them will be used in this particular product.


Comment Re:That's fine and dandy (Score 1) 289

You obviously don't understand SATA3--that's 6GBits/s, which given the encoding used is 600MBytes/s. While I haven't seen the technical details of these 300GB disks, historically the bit density has increased in both dimensions with each new generation of technology. I would also assume that to reach such high capacities they will go multi-layer, which opens the door for parallel reading of all layers. Furthermore, there is a lot of research into multi-track reading and writing technology, where the laser is split into multiple beams which are read back by a linear sensor array. That way a number of adjacent tracks can be read in a single revolution and reconstructed in a buffer into a single data stream that's effectively N times faster, N being the number of tracks. That, plus the higher bit density and multiple layers could come close to saturating the SATA3 bus. I'm sure that the engineers working on 300GB disks haven't sheepishly missed the data transfer bottleneck elephant in the room.

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